Preamplifier circuits can be implemented in a magnetic disk-drive system to generate an overshoot current for writing data to a magnetic medium (e.g., a magnetic disk drive, such as a hard-disk drive). As an example, it can be desirable to tune a pulse duration of the overshoot current, such as greater than a given duration of a data bit as dictated by a write data input signal. For example, it may be desirable to set a duration of the overshoot current to greater than duration of a single bit to provide current overshoot for shorter bit patterns, but not longer patterns, to achieve substantially better data rates for drive optimization. However, for pulse duration control systems that implement delay of the write data input signal, overshoot current pulse durations greater than a single bit can cause unacceptable jitter and bad eye patterns based on delayed write data arriving after the write data input signal has already changed states.